The pilot of a small aircraft descended below the published approach minimum altitude due to VFR con...

Attributes
ACN	1310030
Time
Date	201511
Local Time Of Day	1201-1800
Place
Locale Reference	HIO.Airport
State Reference	OR
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Small Aircraft Low Wing 1 Eng Retractable Gear
Operating Under FAR Part	Part 91
Flight Phase	Initial Approach
Route In Use	Other RNAV GPS 31L
Flight Plan	IFR
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Instrument Flight Crew Private
Experience	Flight Crew Last 90 Days 43 Flight Crew Total 495 Flight Crew Type 185
Events
Anomaly	Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy Inflight Event / Encounter CFTT / CFIT

Narrative:

I was enroute via the RNAV GPS 31L approach into hillsboro; oregon (khio). I was between flowr and nnike when I descended below the minimum segment altitude of 4;000 feet and descended to 2;000 feet. The tower controller appropriately and helpfully advised me of my altitude deviation and I corrected it. The conditions were VMC with flight visibility between 7 and 10 miles. The skies were either clear above me or the ceiling was more than 6;000-7;000 feet. I believe I descended below minimum altitude because I grew complacent due to the good conditions and visibility. Instead of knowing that I was between flowr and nnike where the minimum altitude was 4;000 feet; I believed I was between nnike and intll where the minimum altitude is 2;000 feet.I can prevent the recurrence of this problem by rigorously briefing each approach and maintaining accurate positional awareness.

Original NASA ASRS Text

Title: The pilot of a small aircraft descended below the published approach minimum altitude due to VFR conditions; complacency and situational awareness.

Narrative: I was enroute via the RNAV GPS 31L approach into Hillsboro; Oregon (KHIO). I was between FLOWR and NNIKE when I descended below the minimum segment altitude of 4;000 feet and descended to 2;000 feet. The Tower Controller appropriately and helpfully advised me of my altitude deviation and I corrected it. The conditions were VMC with flight visibility between 7 and 10 miles. The skies were either clear above me or the ceiling was more than 6;000-7;000 feet. I believe I descended below minimum altitude because I grew complacent due to the good conditions and visibility. Instead of knowing that I was between FLOWR and NNIKE where the minimum altitude was 4;000 feet; I believed I was between NNIKE and INTLL where the minimum altitude is 2;000 feet.I can prevent the recurrence of this problem by rigorously briefing each approach and maintaining accurate positional awareness.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.